1. Technical Field
This document relates to devices and methods for the treatment of heart conditions. For example, this document relates to devices and methods for treating heart failure with preserved ejection fraction, including diastolic heart failure, by performing a pericardial modification procedure.
2. Background Information
The pericardium is a thin double-layered fluid filled sac that surrounds the heart and the roots of the aorta, vena cava, and the pulmonary artery. The outer sac is known as the fibrous pericardium. The inner sac is known as the serous pericardium. The serous pericardium consists of a visceral layer portion and a parietal layer portion (“parietal pericardium”). The visceral layer covers the heart and the great vessels. The parietal portion lines the outer fibrous pericardium.
The phrenic nerves course from the brain to the diaphragm. The phrenic nerves provide motor impulses to muscles of the diaphragm, thereby allowing for lung expansion to facilitate breathing. The right phrenic nerve passes underneath the muscles of the neck and bones of the shoulder to the base of the right lung, contacting the heart and the trachea. The left phrenic nerve follows a similar path, passing close to the heart before entering the diaphragm.